Test equipment, and particularly equipment employing electronic circuitry, is often used in hostile environments. To insure the accuracy and reliability of the test equipment, it is frequently necessary to isolate the equipment from exposure to the environment. Furthermore, in addition to isolating the test equipment, provisions must be made to allow ready access to the equipment for servicing and repair. Also, cost will always be a factor in such an application.
The use of electronic circuitry in underwater exploration has been expanding for many years. This electronic circuitry must be protected from the effects of salt water when the circuitry is used in the ocean and must even be protected against contamination by rain, spray, bilge water and grime, all common factors on a seagoing vessel.
One particular electronic device used in underwater exploration is the magnetometer. This device is capable of detecting masses of ferrous metals in the ocean, on the ocean floor and even below the floor of the ocean. It is therefore a very useful instrument in detecting the location of objects underwater. However, such magnetometers must often be lowered from a ship or carried by divers to great depths within the ocean in order to provide adequate sensitivity. Even when a magnetometer can be ship mounted, it is frequently necessary to place it above water at the ship's bow where the effects of the boat's magnetic field and engine ignition noise are minimized, but the spray, breaking swells and rain as the ship drives through the ocean are most significant. Also, magnetometers require frequent service and maintenance and the electronics must be readily accessible. Therefore, a need exists for an apparatus and method to protect such electronic circuitry used underwater.